静态构造函数运行是否作为 CER？

Question

我正在测试以下代码：

private static void Main()
{
    var t = new Thread(() => 
    {
        var m = new MyCls();
        m.DoWork();       
    });
    t.Start();

    // simulate time-consuming job
    Thread.Sleep(1000);

    t.Abort();
    Console.Write("\nDone");
}


public class MyCls
{
    static MyCls()
    {
        for (int i = 0; i < 10; i++)
        {
            Console.Write(i);
            Thread.Sleep(1000);
        } 
    }

    public void DoWork()
    {
        Console.WriteLine("executing DoWork..");
    }
}

我得到的输出是：

0123456789
Done

似乎 t.Abort() 调用阻塞了主线程，直到静态构造函数的执行完成，并且根据 documentation:

The thread that calls Abort might block if the thread that is being aborted is in a protected region of code, such as a catch block, finally block, or constrained execution region.

我的问题是：

静态构造函数真的运行作为受限执行区域 (CER) 吗？
如果是，还有哪些其他代码阻止运行作为 CER？

Answer 1

更新：问题是关于 t.Abort() 阻塞，而不是中断，所以这个答案几乎不相关:)

Thread.Abort Method 的文档明确指出 Abort 可能会中止静态构造函数。

When a thread calls Abort on itself, the effect is similar to throwing an exception; the ThreadAbortException happens immediately, and the result is predictable. However, if one thread calls Abort on another thread, the abort interrupts whatever code is running. There is also a chance that a static constructor could be aborted. In rare cases, this might prevent instances of that class from being created in that application domain.

和

For example, calling Thread.Abort may prevent static constructors from executing or prevent the release of unmanaged resources.

虽然您的示例优雅地表明静态构造函数可能不会被中断，但不能保证这种行为。

更新

这是一个静态构造函数被 Abort() 中断的示例。

代码

public static void Main()
{
    Console.WriteLine($"START");
    var t = new Thread(() =>
    {
        var m = new MyCls();
    });
    Console.WriteLine($"t.Start");
    t.Start();

    Thread.Sleep(2000);
    Console.WriteLine($"Trying to create a new object");

    try
    {
        var m2 = new MyCls();

    }
    catch (Exception ex) { Console.WriteLine(ex); }
    Console.WriteLine("All done");
    Console.ReadLine();
}


public class MyCls
{
    static MyCls()
    {
        for (int i = 0; i < 10; i++)
        {
            if (i == 4)
            {
                Console.WriteLine($"sctor calling Abort on itself");
                Thread.CurrentThread.Abort();
            };
            Console.WriteLine($"sctor.{i}");
            Thread.Sleep(100);
        }
    }
}

输出

START
t.Start
sctor.0
sctor.1
sctor.2
sctor.3
sctor calling Abort on itself
Trying to create a new object
System.TypeInitializationException: The type initializer for 'MyCls' threw an exception. ---> System.Threading.ThreadAbortException: Thread was being aborted.
   at System.Threading.Thread.AbortInternal()
   at System.Threading.Thread.Abort()
   at Program.MyCls..cctor() in c:\users\letss\source\repos\ConsoleApp2\ConsoleApp2\Program.cs:line 42
   --- End of inner exception stack trace ---
   at Program.MyCls..ctor()
   at Program.Main() in c:\users\letss\source\repos\ConsoleApp2\ConsoleApp2\Program.cs:line 21
All done

Answer 2

看来静态构造函数保证已经完成，差不多了。

可以使用 RuntimeHelpers.RunClassConstructor 显式调用静态构造函数，其中'确保指定类型的类型初始值设定项（也称为静态构造函数）已运行'.

在你的例子中，代码可以这样写。

var t = new Thread(() =>
{
  System.Runtime.CompilerServices.RuntimeHelpers.RunClassConstructor(typeof(MyCls).TypeHandle);
  var m = new MyCls();
});

RunClassConstructor 调用 _RunClassConstructor 并用以下注释进行注释。

In the absence of class constructor deadlock conditions, the call is further guaranteed to have completed.

// RunClassConstructor causes the class constructor for the given type to be triggered
// in the current domain.  After this call returns, the class constructor is guaranteed to
// have at least been started by some thread.  In the absence of class constructor
// deadlock conditions, the call is further guaranteed to have completed.
//
// This call will generate an exception if the specified class constructor threw an 
// exception when it ran. 
[System.Security.SecuritySafeCritical]
[ResourceExposure(ResourceScope.None)]
[MethodImplAttribute(MethodImplOptions.InternalCall)]
private static extern void _RunClassConstructor(RuntimeType type);

静态构造函数运行是否作为 CER？

Do static constructors run as CERs?

c#

clr

thread-abort

cer

threadabortexception

更新

代码

输出

静态构造函数 运行 是否作为 CER？

Do static constructors run as CERs?

c#

clr

thread-abort

cer

threadabortexception

更新

代码

输出

静态构造函数运行是否作为 CER？